In the banking service system, the
uncertainty of customer demands, the service
encounters, and customer queries are the major causes
that affect and interfere the stability of teller
performance. The causes are classified as “noise”
to enlarge the variability of teller performance and
these are the sources why the service time in the
system for customer is fluctuant. One of the ways to
enhance the service quality of the banking system is
customer satisfaction; and the customer satisfaction
can be achieved by way of both shortening the expected
service time in the system and realizing the operation
efficiency and stability of service system.

Good
personnel, advanced hardware and effective evaluation
tools are to sustain the stable and efficient service
of the banking system. These special quality
attributes are similar to the concept of the
signal-to-noise ratio. Based on the ratio, we propose
one service index to evaluate the operational
effectiveness of the tellers and the entire banking
system. Procedures are also provided. Through simple
calculation of the average and standard deviation of
the service time, and referring to the tables, the
operational effectiveness of the tellers and the
entire banking system are evaluated. The subjective
and efficient methodology that we propose can be
easily applied to the daily operation management of
the banking system.